Comment on "Information arms race explains plant-herbivore chemical communication in ecological communities"

Zu et al (Science, 19 Jun 2020, p. 1377) propose that an ‘information arms-race’ between plants and herbivores explains plant-herbivore communication at the community level. However, the analysis presented here shows that key assumptions of the proposed model either a) conflict with standard evolutionary theory or b) with our current understanding of plant-insect interactions and phytochemical evolution. We investigate whether specific conditional information might be more suitable as a fitness proxy than the community averages proposed by Zu et al. Finally, we show that the presented statistical patterns can be explained more parsimoniously (e.g. through a null model) without invoking an unlikely process of community selection.